Orthopedic instrumentation

ABSTRACT

An instrumentation system that includes a reamer sleeve having a reamer wall and a wedge body, the reamer wall being oriented about a central longitudinal axis. The reamer wall includes an inner passage that is sized to receive insertion of a reference instrument that is structured for placement in a canal in a bone. The inner passage can be centrally oriented about a longitudinal axis that is offset from at least the central longitudinal axis of the reamer wall. The wedge body can have a wedge surface that extends axially in a direction that is non-parallel and non-perpendicular to the central longitudinal axis. The apparatus also can include a cap having an opening that is sized to receive insertion of the wedge body. The cap can further include an inner wall having a tapered wall section that is oriented to matingly engage the wedge surface of the wedge body.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. National Phase of International PCTApplication No. PCT/US2016/043136 filed on Jul. 20, 2016, which claimsthe benefit of U.S. Provisional Patent Application Ser. No. 62/195,035filed Jul. 21, 2015, the contents of each application herebyincorporated by reference in their entirety.

BACKGROUND

Embodiments of the present invention generally relate to asinstrumentation system for preparation for implantation of a metaphysealand/or diaphyseal implant or augment. More particularly, but notexclusively, embodiments of the present invention relate toinstrumentation that facilitates a degree of positional freedom in theplacement of a metaphyseal and/or diaphyseal implant or augment relativeto a reference axis.

Proper alignment of a replacement joint device, including components ofthe replacement joint device, often may at least assist in attainingoptimal wear resistance and optimal performance of the implanted device.Yet, patient anatomical variations present challenges in properlyaligning the implant device for each patient. For example, duringimplant construct of knee replacement joint, challenges may arise withfitting a patient's intramedullary geometry with an implant, such as,for example, an intramedullary stem, while also fitting both theexternal geometry with a condylar replacing implant and the metaphysealand/or diaphyseal geometry with an associated implant or augmentcomponent. Moreover, the addition, of a metaphyseal and of diaphysealimplant or augment to an implant construct often impairs the ability toadjustably fit the implant to the patient and/or attain proper alignmentfor various components of the implant. Such difficulties may at times beattributed to the anatomy of the patient, the geometrical constraints ofthe implant, and of constraints associated with the preparatoryinstrumentation. For example, geometrical constraints of the metaphysealand/or diaphyseal implant or augment may include the inability of theimplant to accommodate the placement or position of both theintramedullary stem and the condylar implant, which can attribute todifficulties in forming a junction mechanism for those, and possiblyother, components of the implant.

Challenges associated with attaining proper alignment during implantconstruct that involves metaphyseal and/or diaphyseal implants oraugments have, at times, been resolved by compromises in terms of theplacement of at least some components of the implant device, such as,for example, the location of the condylar implant. Yet, such compromisescan result in less than optimal bone coverage, which can potentiallycompromise loading of the construct to the cortical rim of the bone.Other compromises can include reducing the stem size in order to offsetthe stem position, with the area vacated by such offsetting being madeup with cement. Yet, for various reasons, such compromises may adverselyimpact the life of the implant, including being associated with failuresrelating to subsidence, loosening, stress-shielding factors andincreased stresses on the implant device, among other failures.

Therefore, the integrity of the implant construct may be adverselyimpacted if the bone is not shaped, during implant surgery, toaccommodate the positioning of augmenting implants at locations in whichthe implanted augments, such as, for example, stems, sleeves, and cones,among other augments, will not interfere with the articular componentand/or other augmenting implants.

BRIEF SUMMARY

Certain embodiments of the invention may include an apparatus thatincludes a reamer sleeve having a reamer wall and a wedge body, thereamer wall being oriented about a central longitudinal axis. The reamerwall includes an inner passage that is sized to receive insertion of areference instrument that is structured for placement in a canal of abone. The wedge body can extend from a first end wall of the reamer walland can have a wedge surface that extends axially in a direction that isnon-parallel and non-perpendicular to the central longitudinal axis. Theapparatus can also include a cap having an inner wall, at least aportion of the inner wall defining an opening of the cap that is sizedto receive insertion of the wedge body. Additionally, the inner wall canhave a tapered wall section that extends axially in a direction that isgenerally parallel to the wedge surface.

Certain embodiments of the invention may also include a reamer sleevethat is adapted to be positioned about a reference instrument. Thereamer sleeve can include an inner passage and a wedge body, the innerpassage being steed to receive insertion of the reference instrument.The wedge body can extend from a first end wall of a reamer wall of thereamer sleeve and can include an inner surface and a wedge surface atopposing sides of the wedge body. The inner surface of the wedge bodycan be positioned to abut against a portion of the inserted referenceinstrument, while, the wedge surface can be oriented on an incline thatis non-parallel and non-perpendicular to the inner surface.

Additionally, certain embodiments of the invention may include a cap forplacement about a reamer sleeve. The cap can include a cap wall havingan inner side and an outer side, the inner side structured to abutagainst the reamer sleeve. Further, the inner side can define an openingthat axially extends about a central axis. Additionally, the inner sidecan have a tapered wall section that extends along an incline in adirection that is non-parallel and non-perpendicular to the centralaxis. The cap can also include a spline tooth, at least a portion of thespline tooth extending into the opening.

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying figureswherein like reference numerals refer to like parts throughout theseveral views.

FIG. 1 illustrates a side perspective view of an exemplary orthopedicinstrumentation system positioned about a portion of a referenceinstrument according to an illustrated embodiment of the presentinvention.

FIG. 2 illustrates a side perspective view of the orthopedicinstrumentation system of FIG. 1 positioned about a portion of thereference instrument, and with a portion of the orthopedicinstrumentation system at a wedged position in an intramedullary canalof a bone.

FIG. 3 illustrates a side cross-sectional view of a portion of theorthopedic instrument system shown in FIG. 2 at the wedged positionrelative to the canal of the bone.

FIGS. 4A-E illustrate offset and non-offset positions of inner passagesof exemplary reamer sleeves relative to a central axis of the associatedreamer sleeve according to illustrated embodiments of the presentinvention.

FIG. 5 illustrates an end view of a cap positioned about a reamer sleeveaccording to an illustrated embodiment of the present invention.

FIGS. 6A and 6B illustrate side views of a portion of an orthopedicinstrument system at a first, non-wedged position and a second, wedgedposition, respectively, about a reference instrument.

FIG. 7 illustrates a side perspective view of a forming tool positionedabout a reference instrument prior to a forming tool being positionedabout a reamer sleeve of an orthopedic instrument system that isextending into a canal of a bone.

FIGS. 8 and 9 illustrate a side perspective view and a partial cutawayview, respectively, of the forming tool of FIG. 7 positioned about thereamer sleeve of the orthopedic instrument system and a correspondingformed portion of the canal of the bone.

FIG. 10 illustrates a top view of the forming tool shown in FIG. 9 withgenerally common central axes of the reamer sleeve and the forming toolbeing offset from a central longitudinal axis of the referenceinstrument and/or of the canal of the bone.

The foregoing summary, as well as the following detailed description ofcertain embodiments of the present invention, will be better understoodwhen read in conjunction with the appended drawings. For the purpose ofillustrating the invention, there is shown in the drawings, certainembodiments. It should be understood, however, that the presentinvention is not limited to the arrangements and instrumentalities shownin the attached drawings.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Certain terminology is used in the foregoing description for convenienceand is not intended to be limiting. Words such as “upper,” “lower,”“top,” “bottom,” “first,” and “second” designate directions in thedrawings to which reference is made. This terminology includes the wordsspecifically noted above, derivatives thereof, and words of similarimport. Additionally, the words “a” and “one” are defined as includingone or more of the referenced item unless specifically noted. The phrase“at least one of” followed by a list of two or more items, such as “A, Bor C,” means any individual one of A, B or C, as well as any combinationthereof.

FIGS. 1-3 illustrate side perspective and cross sectional views of anexemplary orthopedic instrumentation system 100 positioned about aportion of a reference instrument 102 according to an illustratedembodiment of the present invention. Referencing FIG. 3, at least aportion of the reference instrument 102 can be structured to bepositioned in an intramedullary canal 104 of a bone 110. According tocertain embodiments, the intramedullary canal 104 in which the referenceinstrument 102 is placed can include a prepared portion 106 which cancomprise an area or segment in the bone 110 in which the size of theintramedullary canal 104 was increased by a surgical preparatoryprocedure, such as reaming or drilling, among other bone removalprocedures. For example, in the embodiment depicted in FIG. 3, thewidth, such as diameter, of a portion of the intramedullary canal 104that can be increased to a first width (as indicated, by “w₁” in FIG. 3)to provide a prepared portion 106 of the intramedullary canal 104.According to such an example, the first width of the prepared portion106 of the intramedullary canal 104 can be larger than a correspondingsecond width (as indicated by “w₂” in FIG. 3) of other, non-preparedportions 108 of the intramedullary canal 104, such as portions of theintramedullary canal 104 that were not subjected to the surgicalpreparatory procedure.

At least a portion of the intramedullary canal 104 can be generallylocated about a central location the intramedullary canal 104. Further,the central longitudinal axis 112 of the intramedullary canal 104 may ormay not be at a generally central location along the prepared portion106 of the intramedullary canal 104. For example, in the embodimentshown in FIG. 3, the prepared portion of the intramedullary canal 104 isoffset from the non-prepared portion 106 of the intramedullary canal104. Thus, in at least certain situations, the central longitudinal axis112 of the intramedullary canal 104 can be positioned at a generallycentral position relative to the non-prepared portion 108 of theintramedullary canal 104, while the prepared portion 106 of theintramedullary canal 104 is generally at an offset position relative tothe central longitudinal axis 112.

A variety of different types of instruments or guides can be utilizedfor the reference instrument 102, including, for example, anintramedullary rod, trial stem, reamer, or offset rod, among otherinstruments or guides. According to certain embodiments, the referenceinstrument 102 extends along a central longitudinal axis 114. Further,when positioned in the intramedullary canal 104, the centrallongitudinal axis 114 of the reference instrument 102 may, or may not,generally extend along the central longitudinal axis 112 of the canal104, as demonstrated in FIG. 3. Additionally, according to certainembodiments at least a portion of a first end of the referenceinstrument 102 can structured to be affixed in the intramedullary canal104 of the bone 110. Moreover, according to certain embodiments, thefirst end 103 of the reference instrument 102 can be secured to the bone110 in or adjacent to the non-prepared portion 108 of the intramedullarycanal 104.

The orthopedic instrumentation system 100 can include a guide 116, guidebushing 118, reamer sleeve 120, and cap 122. The guide 116 can include abody portion 124 having opposing first and second sides 126, 128 and anedge 130 that generally define an outer periphery of the body portion124. The guide 116 can also include a handle 132 that outwardly extendsfrom the body portion 124. The handle 132 can be structured to at leastassist in the positioning and/or maintaining a position of at least thebody portion 124 of the guide 116 relative to the bone 110 and/orintramedullary canal 104. According to certain embodiments, the guide116 can be a drill guide or tray profile instrument. Further, accordingto certain embodiments, the handle 132 can be removably coupled to thebody portion 124, such as, for example, by a mating threaded connection.

The guide bushing 118 can include a wall 134 having an inner portion 136and an outer portion 138, and that extends between a second end 140 anda first end 142 of the guide bushing 118. The inner portion 136 of thewall 134 can generally define a bushing aperture 144 of the guidebushing 118 that is sized to receive insertion of at least a portion ofthe reamer sleeve 120. For example, the bushing aperture 144 of theguide bushing 118 can have a size, such as, for example, a diameter,that can receive the placement of at least a portion of the reamersleeve 120 in a manner that accommodates the axial displacement orsliding of the reamer sleeve 120 along the bushing aperture 144, or viceversa, while also minimizing the degree, if any, so which the reamersleeve 120 can be transversally displaced within the bushing aperture144.

The second end 140 of the guide bushing 118 can include an engagementportion 146 that is shaped or configured to facilitate the ability togrip or otherwise manipulate the position of the guide bushing 118.Moreover, the engagement portion 146 can improve a grasp on the guidebushing 118 at least when an angular position of the guide bushing 118is adjusted, such as, for example, an adjustment of the angular positionof at least the guide bushing 118 member relative to at least theintramedullary canal 104 and/or the guide 116. For example, according tothe illustrated embodiment, a portion of the outer portion 138 of thewall 134 of the guide bushing 118 can include a plurality or recesses148 intermixed with a plurality of protections 150 that are structuredto enhance the ability of a user to grasp, and/or retain a grasp of, theguide bushing 118. According to other embodiments, the engagementportion 146 can comprise at least a knurled surface along at least aportion of the outer portion 138 of the wall 134.

The guide bushing 118 is configured to be coupled to the guide 116. Forexample, according to certain embodiments, at least a portion of theouter portion 138 of the wall 134 at the first end 142 of the guidebushing 118 provides an end portion 152 that is configured to bereceived in the aperture 154 of the guide 116. Further, the end portion152 of the wall 134 and the aperture 154 of the guide 116 can beconfigured to minimize the degree, if any, to which the end portion 152can be transversally displaced within the aperture 154 of the guide 116.Further, the guide bushing 118 can be coupled to the guide 116 by atleast one mechanical fastener 156, such as for example, a pin, screw,bolt or clip, among other mechanical fasteners. For example, as shown inFIG. 3, according to the depicted embodiment, the fastener 156 can be aball plunger that threadingly engages at least a threaded portion of anorifice 158 in the guide 116. Further, in the depicted embodiment, theorifice 158 is in communication with the aperture 154 of the guide 116such that the fastener 156 can be displaced via the threaded engagementwith the orifice 158 to a portion in which an end segment 157 of thefastener 156 exerts a force against a portion of the end portion 152 ofthe guide bushing 118. Optionally, according to certain embodiments,rotational displacement or tightening of the fastener 156 can result inthe end segment 157 of the fastener 156 exerting a force against theguide bushing 118 that prevents rotational displacement of the guidebushing 118 relative to at least the guide 116.

In the depicted embodiment, the end portion 152 of the wall 134 of theguide bushing 118 includes a recessed section 160 that can be configuredto facilitate engagement between the fastener 156 and the end segment157 of the fastener 156. For example, in the depicted embodiment, therecessed section 160 includes a radius or opposing angled surfaces thatgenerally mate the radius or configuration at the end segment 157 of thefastener 156. According to certain embodiments, the recessed section 160can be positioned to generally align with the orifice 158 of the guide116, and thus the fastener 156, when a bottom wall 134 at the first end142 of the guide bushing 118 is positioned against a portion of the bone110, as shown for example in FIG. 3. Alternatively, the recessed section160 of the guide bushing 118 can generally align with the orifice 158when a shoulder portion 162 of the wall 134 of the bushing guide 116abuts against the first side 126 of the guide 116, as shown for examplein FIGS. 1-3.

The reamer sleeve 120 includes a reamer wall 164 having an inner side166 and an outer side 168. According to the illustrated embodiment, atleast the outer side 168 of the reamer wall 164 can extend about acentral longitudinal, axis 170. Further, the outer side 168 of thereamer wall 164 is configured to be axially displaced along the bushingaperture 144 of the bushing guide 116, or vice versa, as previouslydiscussed. Thus, the outer side 168 of the reamer wall 164 can have ashape and/or size that generally conforms to the shape and/or size ofthe bushing aperture 144.

Referencing FIGS. 1 and 2, according to the illustrated embodiment, theouter side 168 of the reamer wall 164 can include one or more depthindicators 172. Such depth indicators 172 can provide an indication ofthe depth to which the reamer sleeve 120 has been inserted into anopening in the bone 110. Further, according to certain embodiments, oneor more of the depth indicators 172 can provide an indication of aminimum depth that the reamer sleeve 120 is to be inserted into anopening in the bone 110. The reamer sleeve 120 can also include a recess174 that extends through the outer side 168 and which is configured toassist in removal of the reamer sleeve 120 from the bone 110 and/orguide bushing 118. For example, the recess 174 can be sized to receive aportion of a slide hammer that assists in removal of the reamer sleeve120 from the bone 110 or guide bushing 118.

The inner side 166 of the reamer sleeve 120 can generally define aninner passage 176 that is configured to receive insertion of at least aportion of the reference instrument 102. Moreover, the inner passage 176can have a cross sectional size and/or shape that is similar to that ofthe reference instrument 102. For example, according to certainembodiments, the inner passage 176 can have a size that accommodatesaxial displacement of the reamer sleeve 120 along the referenceinstrument 102 and which also limits the extent, if any, that the reamersleeve 120 can be transversely displaced about the received referenceinstrument 102.

As shown in FIGS. 4A-4E, the inner passage 176 can extend along alongitudinal axis 178. When the reamer sleeve 120 is positioned aboutthe reference instrument 102, the longitudinal axis 178 of the innerpassage 176 can generally align with the central longitudinal axis 114of the reference instrument 102. Additionally, the longitudinal axis 17Bof the inner passage 176 may, or may not, be offset from a centrallongitudinal axis 170 of the reamer sleeve 120. Such similarities and/ordifferences in the relative positions of the longitudinal axis 178 ofthe inner passage 176 and the central longitudinal axis 170 of thereamer sleeve 120 can allow for adjustment in the position of theforming tool 180 (FIGS. 8-10) relative to one or more referenceaxis(es), such as, for example, the central longitudinal axis 114 of thereference instrument 102 and/or the central longitudinal axis 112 of theintramedullary canal 104, as discussed below. Moreover, as discussedbelow, as the forming tool 180 can be generally centrally positionedabout the reamer sleeve 120, adjustments in the position of the centrallongitudinal axis 170 of the reamer sleeve 120 relative to thelongitudinal axis 178 of the inner passage 176 can adjust the positionat which the forming tool 180 removes bone material relative to thecentral longitudinal axis 112 of the intramedullary canal 104 and/or thecentral longitudinal axis 114 of the reference instrument 102.

As shown in FIG. 4A, according to certain embodiments, the longitudinalaxis 178 of the inner passage 176 can generally align with the centrallongitudinal axis 170 of the reamer sleeve 120. Moreover, as previouslydiscussed, in such situations, the central longitudinal axis 170 of thereamer sleeve 120 can be generally aligned with a reference axis, suchas the central longitudinal axis 112 of the intramedullary canal 104,the central longitudinal axis 114 of the reference instrument 102,and/or longitudinal axis 178 of the inner passage 176. Thus, in suchsituations, and as discussed below, bone material that is subsequentlyremoved from the bone 110 by operation of the forming tool 180 cangenerally be located at a position in the bone 110 that is generallyaligned with the central longitudinal axis 170 of the reamer sleeve 120,as well as the central longitudinal axis 112 of the intramedullary canal104, the central longitudinal axis 114 of the reference instrument 102,and/or the longitudinal axis 178 of the inner passage 176.

According to other embodiments, the position of the longitudinal axis178 of the inner passage 176 can be offset from the central longitudinalaxis 170 of the reamer sleeve 120 along a first axis (as indicated bythe “X” direction in FIG. 4B) and/or a second axis (as indicated by the“Y” direction in FIG. 4C). Further, the longitudinal axis 178 of theinner passage 176 can be offset from the central longitudinal axis 170of the reamer sleeve 120 in directions that are a combination of thesetwo axes (e.g., “X” and “Y” axes in FIGS. 4B and 4C, respectively),among other axes, as shown for example by FIG. 4D. Such freedom canallow for the forming tool 180 to form an opening, or formed portion inthe bone 110 at a location that can improve the alignment of thesubsequently implanted orthopedic device and/or prevent an implantedaugment from touching another component of the implant device, such as,for example, an augment touch a tibial stem or a tray stent that extendsfront a tibial tray.

In addition to displacement along at least two axes, such as, forexample, along the “X” and “Y” axes shown in FIGS. 4B and 4C,respectively, and/or a combination thereof, according to certainembodiments, the inner passage 176 of the reamer sleeve 120 can alsoallow for at least a degree of adjustment or displacement in the angularorientation of the reamer sleeve 120 about the reference instrument 102,as indicated, for example, by a comparison of FIGS. 4D and 4E. In atleast certain situations in which the longitudinal axis 178 of the innerpassage 176 is offset from the central longitudinal axis 170 of thereamer sleeve 120, such angular displacement can allow at leastadjustment in the location of the longitudinal axis 178 of the innerpassage 176 relative to at least the central longitudinal axis 112 ofthe intramedullary canal 104, and thereby adjust the location at whichthe forming tool 180 forms the formed portion in the bone 110. Accordingto certain embodiments, the angular orientation of the centrallongitudinal axis 170 of the reamer sleeve 120 can be adjusted around360 degrees relative to at least the location of the longitudinal axis178 of the inner passage 176 and the central longitudinal axis 112 ofthe intramedullary canal 104.

As shown by FIGS. 1 and 4A-4E, the outer side 168 of the reamer sleevewall 164 can include an orientation indicator 182 that assists inproviding an indication of the rotational position of at least thereamer sleeve 120. The orientation indicator 182 of the reamer sleeve120 can take a variety of forms, including, for example being a slot,groove(s), recess, or protrusion. Further, according to certainembodiments, the orientation indicator 182 of the reamer sleeve 120 canform or be provided with or as indicia, such as a shape(s), letter(s),and/or number(s) that provides an indication of the angular position ofat least the reamer sleeve 120. Additionally, according to certainembodiments, an upper wall 184 of the guide bushing 118 can also includean orientation indicator 186 that can generally align with theorientation indicator 182 of the reamer sleeve 120. For example, asshown in FIGS. 1 and 3, the orientation indicator 186 of the guidebushing 118 can be a slot, recess, groove, and/or indicium, such as ashape, that provides an indication of the angular orientation of atleast the reamer sleeve 120. According to certain embodiments, theorientation indicators 182, 186 of the reamer sleeve 120 and the guidebushing 118 can be generally aligned by alignment of keyways of thereamer sleeve 120 and the guide bushing 118. Further, according tocertain embodiments, the orientation indicator 182 of the reamer sleeve120 can be a keyway that, when aligned with a keyway of the guidebushing 118, is generally aligned with the orientation indicator 186 ofthe guide bushing 118. Further, according to certain embodiments, theorientation indicators 182, 186 of the reamer sleeve 120 and the bushingguide 116 can generally be rotated to align with different angularposition indicators, for example, numbers, among other angular positionindicators, that are arranged on the first side 126 of the guide 116.

The outer side 168 of the reamer sleeve 120 can also include a relief188 that can provide a location for information identifying the reamersleeve 120. For example, the relief 188 can provide a location, at whichthe part number of the reamer sleeve 120 and/or information regardingthe offset, if any, provided by the longitudinal axis 178 of the innerpassage 176, among other information. The relief can be recessed in theouter side 168 of the reamer sleeve 120 so as to at least attempt toprevent damage to the relief 188 that could adversely impact theinformation contained in the relief 188. For example, the relief 188 canhave a depth into the reamer sleeve 120 that positions information inthe relief 188 at a location that can prevent that information frombeing removed or adversely effected by wear or usage of the reamersleeve 120.

Referencing FIGS. 3, 5, 6A, and 6B, the exemplary reamer sleeve 120 canfurther include a wedge body 190 that extends from a first end wall 192of the reamer sleeve wall 164. The wedge body 190 can be configured toextend around at least a portion, if not all, of an adjacent section ofthe reference instrument 102. For example, according to certainembodiments, as indicated by FIG. 5, the wedge body 190circumferentially extends between first and second sidewalls 194, 196 ofthe wedge body 190, the first and second sidewalls 194, 196 beingseparated by an axially extending slot 198. Additionally, according tocertain embodiments, the wedge body 190 can include an inner surface 200that generally has a similar configuration as the inner side 166 of thereamer sleeve 120. Moreover, the inner surface 200 of the wedge body 190is configured to abut against an adjacent surface of the referenceinstrument 102. Thus, according to the illustrated embodiment, the innersurface 200 of the wedge body 190 can axially extend in a direction thatis generally parallel to the central longitudinal axis 170 of the reamersleeve 120.

The wedge body 190 can further include a wedge surface 202 that istapered or angled relative to at least the inner surface 200 of thewedge body 190. Moreover, as shown by at least FIGS. 6A and 6B, in theillustrated embodiment, the wedge surface 202 of the wedge body 190axially extends in a direction that is non-parallel to the centrallongitudinal axis 170 of the reamer sleeve 120. Thus, the wedge body 190can generally have a thickness between the inner and wedge surfaces 200,202 at a first end 206 of the wedge body 190 that is less than acorresponding thickness between the inner and wedge surfaces 200, 202 ata second end 204 of the wedge body 190.

According to certain embodiments, a first end wall 192 of the reamersleeve wall 164 can extend at an incline that is generally perpendicularto the axial direction of wedge surface 202, as shown for example inFIGS. 6A and 6B. According to such an embodiment, this portion of thefirst end wall 192 of the reamer sleeve 120 non-perpendicular, andnon-parallel to the central longitudinal axis 170 of the reamer sleeve120 and/or the longitudinal axis 178 of the inner passage 176.

The wedge surface 202 of the wedge body 190 can also include a cavity208 that is configured to accommodate displacement of at least the wedgebody 190 relative to a retainer 210 of the cap 122, as discussed below.The cavity 208 can extend between first and second shoulders 212, 214 ofthe cavity 208. The first and second shoulders 212, 214 can extend froma base wall 213 of the cavity 208 by a length that accommodatesslideable displacement of the retainer 210 within the cavity 208, andwhich can also assist in retaining the retainer 210 within the cavity208. Further, according to certain embodiments, the cavity 208, and thusthe first and second shoulders 212, 214, can extend along the wedge body190 at an angle that is generally perpendicular to the angle oforientation of the wedge surface 202.

The cap 122 includes a cap wall 210 having an inner side 218 and anouter side 220. The outer side 220 can be configured for placementagainst a bone 110 when the cap 122 is positioned within theintramedullary canal 104 and/or in a prepared opening in the bone 110.According to certain embodiments, the outer side 220 is configured toenhance the engagement between the order side 220 of the cap 122 andadjacent bone material. For example, according to certain embodiments,the outer side 220 of the cap wall 216 includes a plurality ofprotrusions 222 or a knurled surface that engages the adjacent bonesurface in a manner that can assist in preventing displacement of thecap 122. According to other embodiments, the protrusions 222 can deformor be compressed when the cap 122 is operably positioned in theintramedullary canal 104 or a prepared opening such that the cap 122 issubjected to a force by adjacent bone material that at least assists inpreventing displacement of the cap 122.

The inner side 218 of the cap 122 generally defines an opening 223 ofthe cap 122 that is sized to receive insertion of at least the wedgebody 190 of the reamer sleeve 120 and the reference instrument 102.Further, at least a portion of the inner side 218 of the cap wall 216includes a tapered wall section 224 that is configured to matinglyengage the wedge surface 202 of the wedge body 190. Thus, in theillustrated embodiment, the tapered wall, section 224 has an angularorientation similar to that of the wedge surface 202. Thus, when the cap122 is operably position about the reamer sleeve 120, the tapered wallsection 224 is non-parallel to the central longitudinal axis 170 of thereamer sleeve 120.

According to the illustrated embodiment, the cap 122 includes a splinetooth 226 that extends into at least a portion of the opening 223 of thecap 122. The spline tooth 226 is sized for placement within the axiallyextending slot 198 between the first and second sidewalls 194, 196 ofthe wedge body 190. The spline tooth 226 can include a pair of opposingsidewalls 228, 230 with one of each of the opposing sidewalls 228, 230positioned adjacent to the first and second sidewalls 194, 196,respectively, of the wedge body 190. Further, as shown in FIGS. 5, 6Aand 6B, according to certain embodiments, the spline tooth 226 includesan inner wall 232 is configured to abut against the reference instrument102. In the illustrated embodiment the inner wall 232 is a curvedsurface that generally conforms to the shape of the adjacent surface ofthe reference instrument 102.

The cap 122 further includes a groove 234 that extends into the innerside 218 of the cap wall 216. The groove 234 is configured to retain theretainer 210, such as, for example a retaining clip, among otherretainers. According to certain embodiments, the retainer 210 is aC-shaped retaining clip. Additionally, according to certain embodiments,the retainer 210 is configured to extend from about the first sidewall194 to the second sidewall 196 of the wedge body 190, or in an areabetween the first and second sidewalls 194, 196. Additionally, thegroove 234 can extend in a direction that is generally perpendicular tothe direction of the tapered wall section 224 of the inner side 218 ofthe cap wall 216 and/or of the wedge surface 202 of the wedge body 190.Moreover, the groove 234 in the cap 122 can be non-perpendicular, andnon-parallel to a central axis 236 of the cap 122. Further, the cap 122can be positioned about the reamer sleeve 120 such that the central axis236 of the cap 122 is generally aligned with the central longitudinalaxis 170 of the reamer sleeve 120, as indicated by FIGS. 9 and 10.

The cap 122 can include opposing upper and lower walls 238, 240. Thelower wall 240 can be configured to engage or abut against bone materialin the intramedullary canal 104 or another opening in the bone 110. Theupper wall 238 can be configured to engage the first end wall 192 of thereamer sleeve wall 164. Accordingly, the upper wall 238 of the cap 122can extend at an incline that is generally parallel to the incline ofthe first end wall 192 of the reamer sleeve 120. Moreover, similar tothe first end wall 192 of the reamer sleeve 120 and the groove 234 ofthe cap 122, the upper wall 238 of the cap 122 can extend along anincline that is generally perpendicular to the incline of the taperedwall section 224 of the inner side 218 of the cap wall 216 and/or of thewedge surface 202 of the wedge body 190. Thus, according to such anembodiment, the upper wall 238 of the cap 122 is non-perpendicular, andnon-parallel to the central axis 236 of the cap 122.

During installation in a bone 110, the reamer sleeve 120 and cap 122 canbe axially displaced along the reference instrument 102 and into theintramedullary canal 104 or other prepared opening in the bone 110.During at least the initial stages of installation, the cap 122 can beat a first position relative to the reamer sleeve 120, and moreoverrelative to the wedge body 190, as shown in FIG. 6A. With the cap 122 atthe first position, the retainer 210 can be positioned adjacent to,and/or against the first shoulder 212 and within the cavity 208 of thewedge body 190. Axial displacement of the cap 122 and the reamer sleeve120 into the intramedullary canal 104 or a prepared opening in the bone110 can continue until the cap 122 encounters resistance, such as thelower wall 240 of the cap 122 abutting a portion of the bone 110, whichprecludes further axial displacement of the cap 122. While axialdisplacement of the cap 122 can stop, at least the reamer sleeve 120 cancontinue to be axially displaced. During such displacement, the wedgebody 190 can continue to be displaced relative to, and/or against, boththe tapered wall section 224 of the cap 122 and the reference instrument102. During such displacement, the location of the retainer 210 withinthe cavity 208 of the wedge body 190 can change, as the second shoulder214 of the cavity 208 can be moved into closer proximity to the retainer210. Further, the relative position of the spline tooth 226 in theaxially extending slot 198 between the first and second sidewalls 194,196 of the wedge body 190 can change as axial displacement of the reamersleeve 120 proceeds. Such axial displacement of the reamer sleeve 120can continue until the wedge body 190 is at a second position relativeto the tapered wall section 224. The reamer sleeve 120 can reach thesecond, wedge position when the wedge body 190 is slid to a position inwhich the perpendicular forces between the wedge body 190 and thetapered wall section 224, as well, as the forces exerted on the wedgebody 190 by the reference instrument 102, prohibit continued axialdisplacement of the reamer sleeve 120 relative to the cap 122. Accordingto the illustrated embodiment, with the cap 122 at the second, wedgedposition relative to the reamer sleeve 120, the retainer 210 can bepositioned within the cavity 208 in relative close proximity to thesecond shoulder 214, as shown by FIG. 6B. However, according to otherembodiments, the distance between the retainer 210 and the secondshoulder 214 can be adjusted by an increase in the distance between thefirst and second shoulders 212, 214.

With the cap 122 at the second position, at least a portion of the firstend wall 192 of the reamer sleeve 120 can be pressed against theadjacent upper wall 238 of the cap 122. Further, the degree to which thefirst end wall of the reamer sleeve 120 abuts the upper wall 238 of thecap 122 can be enhanced by the first end wall 192 and the upper wall 238each being configured to extend along similar inclines, and moreoverinclines that are generally perpendicular to the inclined orientation ofthe tapered wall section 224 of the cap 122 and/or the wedge surface 202of the wedge body 190, as previously discussed.

With the reamer sleeve 120 secured coupled to the cap 122 and with thecap 122 secured to the bone 110 and about the reference instrument 102,the guide 116 and guide bushing 118 can be removed from engagement withthe reamer sleeve 120. Referencing FIGS. 8 and 9, with the guide 116 andguide bushing 118 removed, the forming tool 180 can be displaced alongthe reference instrument 102 and/or the reamer sleeve 120 until theforming tool 180 is positioned adjacent to the bone 110. As shown inFIGS. 9 and 10, with the forming tool 180 positioned about the reamersleeve 120, a central axis 242 of the forming tool 180 can be generallyaligned with, or at the same location, as the central longitudinal axis170 of the reamer sleeve 120. Thus, in situations in which an offsetreamer sleeve 120 is utilized, such as the reamer sleeve 120 illustratedin FIG. 10, the central axis 242 of the forming tool 180 can similarlybe offset from a reference axis, such as, for example, offset from thelongitudinal axis 178 of the inner passage 176 of the reamer sleeve 120the central longitudinal axis 112 of the intramedullary canal 104,and/or the central longitudinal axis 114 of the reference instrument102. Such a configuration can facilitate the formation of a formedportion of an opening in the bone 110 that has a selected degree ofoffset from at least the intramedullary canal 104, as depicted in FIG.9. Moreover, as previously discussed, such offsetting can accommodatethe central axis 242 of the forming tool 180 being offset along at leasttwo axis relative to the intramedullary canal 104, as well asaccommodate angular adjustment of such offsetting relative to at leastthe central longitudinal axis 112 of the intramedullary canal 104.

While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiment(s), but on the contrary, is intended to covervarious modifications and equivalent arrangements included within thespirit and scope of the appended claims, which scope is to be accordedthe broadest interpretation so as to encompass all such modificationsand equivalent structures as permitted under the law. Furthermore itshould be understood that while the use of the word preferable,preferably, or preferred in the description above indicates that featureso described may be more desirable, it nonetheless may not be necessaryand any embodiment lacking the same may be contemplated as within thescope of the invention, that scope being defined by the claims thatfollow. In reading the claims it is intended that when words such as“a,” “an,” “at least one” and “at least a portion” are used, there is nointention to limit the claim to only one item unless specifically statedto the contrary in the claim. Further, when the language “at least aportion” and/or “a portion” is used the item may include a portionand/or the entire item unless specifically stated to the contrary.

The invention claimed is:
 1. An apparatus, comprising: a referenceinstrument arranged and configured to be positioned in an intramedullarycanal of a bone during use; a reamer sleeve having a reamer wall and awedge body, the reamer wall oriented about a central longitudinal axis,the reamer wall having an inner passage sized to receive insertion ofthe reference instrument the wedge body extending from a first end wallof the reamer wall, the wedge body having a wedge surface that extendsaxially in a direction arranged non-parallel and non-perpendicular tothe central longitudinal axis; a cap having an inner wall, at least aportion of the inner wall defines an opening of the cap sized to receiveinsertion of the wedge body, the inner wall having a tapered wallsection that extends axially in a direction arranged generally parallelto the wedge surface; and a forming tool including an opening arrangedand configured to be positioned about the reamer sleeve, the formingtool including a distal end portion arranged and configured to removebone material.
 2. The apparatus of claim 1, wherein the cap comprises anupper wall having an incline arranged generally perpendicular to thetapered wall section, and wherein the first end wall of the reamer wallhas an incline arranged generally perpendicular to the wedge surface. 3.The apparatus of claim 1, wherein the inner wall of the cap comprises agroove having a retainer, the retainer structured to retain the cap inengagement with the wedge body.
 4. The apparatus of claim 3, wherein thegroove is oriented along an incline arranged generally perpendicular tothe tapered wall section.
 5. The apparatus of claim 3, wherein the wedgebody further comprises a cavity sized to receive displaceable insertionof at least a portion of the retainer.
 6. The apparatus of claim 1,wherein the wedge surface extends between a first sidewall and a secondsidewall, the first and second sidewalls separated at least by anaxially extending slot.
 7. The apparatus of claim 6, wherein the capincludes a spline tooth structured for placement in the axiallyextending slot.
 8. The apparatus of claim 1, wherein the inner passageis centrally positioned about a longitudinal axis offset from thecentral longitudinal axis of the reamer wall.
 9. The apparatus of claim1, wherein an outer side of the reamer wall is sized to be receivedwithin the opening of the forming tool.